Locking means for joining sheet material



Dec. 7, 1937. M. 1. WILLIAMSON 2,191,3 93

LGCKING MEANS FOR JOINING SHEET MATERIAL Filed Oct. 1, 1935 2 Sheets-Sheet l INVENTOR, mnall LWilham-son ,Y l 4 H15 QETORNEY Dec. 7, 1937. M. I. WILLIAMSON LOCKING MEANS FOR JOINING SHEET MATERIAL Filed Oct. 1, 1935 2 Sheets-Sheet 2 INVENTOR Patented Dec. 7, 1 937 I UNITED STATES PATENT OFFICE LOCKING MEANS FOR JOINING SHEET MATERIAL Marshall I. Williamson, Edgewater, N. J.

Application October 1, 1935, Serial No. 43,029

4 Claims. (Cl. 229-27) I My invention relates to locking means for join- The group of figures comprising Figs. 5, 6, 7-, 8, ing sheet material, and to structure wherein the 9 and 10 show my locking means as it may be emlocking means are utilized in a novel manner. ployed as a fastener in a carton having a' more More particularly, my invention relates to selfcomplex structure. adjusting, coordinated locking means applicable More particularly; 5 to material such as paper, and other material Fig. 1 is a perspective view, of a simple compossessing suitable stiffness in sheet form, and mercial carton formed of a single blank of sheet is particularly applicable to the manufacture of material, employing my locking means to keep it folding cartons, and the like, inclusive of displays securely fastened in carton form.

adapted to contain merchandise or otherwise pro- Fig. 2 is a plan view of the outer face of the 10 viding for special relationship of parts of the blank of the same carton, shown in Fig. 1, as it same. appears before folding into carton form, the in- Commercial. embodiments of my invention, say dividual male and female members of my lockof the folding carton type, embody compleing means being clearly shown as they appear mentary coordinated locking members usually before inter-locking. I having arcuate or other. non-rectilinear con- Fig. 3 is a perspective view of inter-locking tour, each member comprising both a male and sections of the carton shown in Fig. 1 with nona female element, the female element of one essential portions broken away. The individual member being adapted to receive in coordilocking members are shown ready for immediate nating relationship, the male member of the inter-locking. g 20 other and vice-versa, and the material of such Fig. 4 is ahorizontal section of a carton similar male and female locking elements when .asto that shown in Fig: 1 but having a trapezoidal sembled, as in setting up the carton or the like, cross-section rather than rectilinear. effecting self-limiting adjustment of the thus Fig. 5 is a. perspective view of a compartmented assembled parts and also mutual bracing of the carton also formed of a single blank of sheet ma- 25 directly associated parts and therewith of the terial, and employing my locking means to keep carton or the like as an entirety. My invention it and its integral partition securely fastened in therefore enables the manufacture of folding carton form.

cartons, displays, and the like, inclusive of com- Fi 6 is a horizontal section taken on the line partmented structural forms of same, without the 66 of Fig. 5. 30 use of adhesive. Fig. 7 is a plan view of the inner face of the Advantageously, such male and female locking blank of the carton shown in Fig. 5, as it appears elements are had by slitting or otherwise 0011- before folding into carton form. touring the sheet material at points wholly in- Fig. 8 is a perspective view of interlocking seceluded by, and spaced apart from, its bounding tions of the carton shown in Fig. 5 with non- 35 edges, whereby each male element, upon slight essential parts broken away. The material surpressing, is flexed free from its associated female rounding the male element is shown bent at element, and is thus prepared for insertion withright-angles on a line coincident with the base of in and in interlocking relation with, the female the male member thus preparing the male memelement associated with the other male element. ber for insertion in the female member and at 4 Coincident with the mechanical advantages atthe same time forming an integral compartment tending the various embodiments of my invenwall which is buttressed against dislodgment tion, the locking members may be variously conwithin the carton when assembled. toured to form, for example, a heart or other Fig. 9 is a perspective view similar to that outline bestowing decorative values, to the resultshown in Fig. 8 but having the locking means 45 mg union of the locking member. each contoured to form one half of a heart.

An understanding of the important features of Fig. 10 is a side elevation looking in the direcmy invention can be best obtained by considering tion of the arrow A in Fig. 9 and showing the a few of the various commercial embodiments in ornamental configuration of a heart formed on 60 which it may appear. an outer side wall of the carton, the locking mem- In the accompanying drawings, the group of hers being in their locked position. figures comprising Figs. 1, 2, 3, and 4 show my Referring to the drawings, and particularlyto self-adjusting coordinated locking means as itthe figure group, comprising Figs. 1, 2, 3 and 4, may be employed as a fastener in the constructhe numeral I D, Fig. 2 indicates a blank stamped,

tion of a simple carton. or otherwise out, from sheet material in such a 5 form and including such lineal impressions or scores as to prepare it for folding into a carton adapted to receive and retain suitable contents. The blank illustrated is of an ordinary simple type, and is shown with the usual integrally related, elementary carton elements marked oil on its face by dotted lines.

With reference to both Fig. 1 and Fig. 2, the above mentioned carton elements include a front panel II, which may have an indenture Ila located at its upper end to facilitate opening of the carton when the top is closed; a rear panel l2, having as an integral extension of its upper end, a closure member comprising a top panel I21: and an insert tab lib, and as an integral extension of its lower end a similar closure member comprising a bottom panel I20 and insert tab l2d; an enclosed side panel I3, having as integral extensions of its upper and lower ends the closure-supporting flaps Na and I3!) respectively; an inter-locking side panel H, having as integral extensions of its upper and lower ends the closure-supporting fiaps Ma and llb respectively; and a second inter-locking side panel I5.

Ordinarily such a blank as shown in Fig. 2, and above described, would be made up into carton form by suitably bending on the dotted lines, gluing the interlocking side panels I and I5 together, and closing the top and bottom in the usual well-known manner.

By use of my self-adjusting coordinated locking means, however, gluing, or the use of any adhesive, may be dispensed with entirely, and the finally assembled carton will still present a strong, tight, and well-secured joint as shown at It, Figs. 1 and 4.

My locking means is composed of two individual inter-locking members such as shown at H and I8, Figs. 2 and 3, preferably of an arcuate or other non-rectangular contour; each of which, in turn, is composed of both a female element Ila and l8a respectively, and a male element Nb and and I8!) respectively, and is formed as an integral portion of its respective panel, in this case the interlocking side panel H or l5, by making an arcuate or other suitably contoured cut or slot in the material forming the panel.

These interlocking members, and component elements thereof, are preferably identical in contour with each other although necessarily so, only as to portions having a definite coacting relationship when in interlocked position, and have configurations directly opposed to each other. They are placed in their respective panels in such a manner that, when these panels are in the position assumed immediately prior to interlocking, the outer edge of one male member is directly opposed to, and is in proximate alignment with the outer edge of the other male element. This is well illustrated in Fig. 3.

The proximate alignment of these male elements when in the aforesaid position may be obtained by causing a slight planar displacement from their respective panels, and towards each other, of the outer edges of the male elements.

The planar displacement may be caused by gently pushing or punching the male elements so that their outer edges are out of planar coincidence with the surrounding panel material.

In order to complete the interlocking of the two panels, the planar displacement of the male element of each locking member is increased to such a degree that its associated female element, defined by the outer edge material of the male element and the inner edge of the immediately adjacent panel material, is opened to an extent suificient to admit the male element of the other locking member. The two panels are then slid across each other in such a manner and to such an extent that the juncture points of the male and female elements, as at llc, lid, of one looking member, are fitted tightly against the juncture points of the male and female elements, as atlBc, lad, of the other locking member.

The permanence of the joint so formed will depend a great deal on the suitable tensioning or positioning of the panels which contain the individual locking members. To illustrate; the panels containing the joint IS in Fig. 1 are so positioned with respect to each other, and to the remaining component carton structure, as to be secure against and resist any attempt to collapse the assembled carton by either pulling the front and rear panels in opposite directions, or by pushing them together. The only practical way the carton may be disassembled is by opening both of the end closures, flattening the body on the fold lines, and sliding the male elements out from coordinated relationship with the female elements. Thus the inherent tightness and secureness of the joint i6 can be readily appreciated.

The advantage of using my locking means as a fastening device for cartons can be most fully realized by noting its application to a carton having certain non-rectilinear polygonal forms, that shown in Fig. 4 having the geometrical form in cross-section of a trapezoid, but being in every other way similar to the one forming the subject of the above discussion, and having similar reference numerals for identical parts, with the addition, however, of a "prime" mark to each numeral.

In this particular type of box, because of its geometrical form and consequent location of fold lines, it is impossible to glue or otherwise permanently fasten the carton in its final form before shipping, and still retain the spacial shipping advantage of a collapsible flat form. However, if my locking means is employed as a fastening device, the carton may be shipped in the form of a blank and be easily set up in carton form at the point of ultimate utilization.

Referring now to the figure group comprising Figs. 5, 6, 7, 8, 9 and 10, and showing my locking means applied to one type of compartmented carton; the numeral 20, Fig. 7, indicates a carton blank, in many respects similar to that shown in Fig. 2, but having such an outline and such lineal impressions or scores as fit it for final assembly into a compartmented carton.

The various integrally related structural elements of the blank 20 in this particular instance includez-an exterior panel 2|, having as an integral extension of its upper end, a closure portion consisting of a compartment top panel Ila and insert tab 2| b, and as an integral extension of its lower end, a closure portion comprising a bottom panel Zlc and an insert tab 2|d; a second exterior panel 22 having as an integral extension of its upper end a closure portion consisting of a compartment top panel 22a and an insert tab 22b; an exterior, interlocking side panel 23 having as an integral extension of its upper end a medially split flap portion comprising the compartment-closure supporting flaps 23a and 23b, and as an integral extension of its lower end, the closure supporting flap 230; a second exterior interlocking side panel 24 having as an integral extension of its upper ends. medially split flap portion comprising the compartment-closure supporting flaps 24a and 24b, and as an integral extension of its lower end the closure supporting flap 240; an interior partition panel 25 having at its upper end the indenture 25a, and having as an integral extension of its lower end a closure portion consisting of the bottom panel 25b and insert tab 250; an interlocking internal side panel 26; and a second interlocking internal side panel 21.

Positioned in the outer side panel 23 and at an edge of the interior partition panel 25 are individual members 28 and 29, respectively, of my locking means as shown and described in Fig. 2. Likewise, positioned in the outer side panel 24 and at an edge of the interior partition panel 25 are individual members 30 and 3|, respectively,

of another of my locking means.

These locking means are similar in nature and function to those shown in Fig. 2, with the exception that the individual members 29 and 3|, have male elements which are prepared for interlocking, as in Figs. 8 and 9, by bending the surrounding panel material, at right-angles, on a line coincident with the base of the male element. In this way the interior partition panel 25 is firmly positioned between the exterior panels 2| and 22 to form the two compartments 32 and 33, Fig. 6, in the completely assembled carton.

The positioning of the panels, containing my locking means with respect to the other component parts of the carton, should be particularly noted. As clearly shown in Fig. 6, supplemented by reference to Figs. 8 and 9, the locking means, which serve to hold the partition panel 25 firmly in place, is secured against unlocking by the buttressing pressure-fit of the interior side panel 21 against the exterior panel 2|.

Conceivably, a partition panel such as that shown at 25, and including individual locking members, might be made as a separate blank to be fitted when desired into coordinating locking members provided in an assembled carton. Also, a carton such as that shown in the first figure group might if desired, be formed of two separate blanks fastened together, in assembled form, by my locking means.

As illustratedin Figs. 9 and 10, where parts corresponding tothose shown in Fig. 8 are designated by like reference numerals with the addition of a "prime thereto, individual locking members of my locking means may be given such a contour as will result in an ornamental configuration when in their interlocking position; that shown in Fig. 2, and representing only one instance of the above, being heart-shaped.

My locking means is particularly suitable for use as a fastener for cartons or displays as I sembled from a blank form, but its use is by no means restricted thereto. Advantageous applications of my locking means in any desired number or forms may be found wherever the desire is to join a plurality of sheets of material, of such stiffness that the individual locking members can hold substantially their original contour while employed in an inter-locking capacity, and in such a manner that the individual sheets can be suitably tensioned or positioned to prevent unlocking of the resulting joint.

Whereas I have described my invention by reference to specific forms thereof, it will be understood that many changes and modifications may be made without departing from the spirit of the invention.

I claim:

1. A structure embodying a prepared blank of foldable sheet material, said blank comprising a series of panels related in integral sequence, locking means for joining certain of the said panels in effecting assembly of the structure, said locking means comprising at least one set of two individual locking members provided for mutual coordination, each locking member being formed integral with, and surrounded by, the sheet material of the blank, and each locking member, further, comprising both a male and a female formation, the male formation of one of a set of members being adapted for locking coordination with the female formation of the other of the set of members, so that the bases of the respective male members provide mutually limiting stops, the respective male members being of substantially equalextensions, and said individual locking members of the set being disposed in such relation to their respective panels that an edge of one of such panels lies parallel to and in abutting relation with the line 01 fold.

defining an edge of the other of such panels at which the latter is integrally related to the component structure.

2. A compartmented structure embodying a prepared blank of foldable sheet material, said blank comprising a series of panels related in integral sequence and folded in general spiral formation to provide compartments for the resulting structure, locking means disposed in a pair of contiguously positioned panels to secure such panels to each other and to retain the structure in assembled status, said locking means comprising at least one set of two individual locking members provided for mutual coordination, each locking member being formed integral with, and surrounded by, the sheet material of the blank, and each locking member, further, comprising both a-male and a female formation, the male formation of one of a set of members being adapted for locking coordination with the female formation of the other of the set of members, so that the bases of the respective male members provide mutually limiting stops, the respective male members being of substantially equal extensions, and said individual locking members of the set being disposed in such relation to their respective panels that an edge of one of such panels lies parallel to and in abutting relation with the line of fold defining the edge of the other of such panels at which the latter is integrally related to the component structure.

3. A carton embodying a prepared blank of foldable sheet material, said blank having a peripheral configuration and fold lines across its body to form a set of serially, integrally related lateral panels and closure members for the carton extending respectively from the top and from the bottom of appropriate lateral panels, those individual lateral panels forming the free ends of the serial connection being mutually interlocked to resist unlocking during use and to provide a buttressing reinforcement for the resulting interlocked lateral panel of the final carton, the interlocking means comprising at least one set of two individual locking members formed respectively in the free ends of the serial connection of panels wholly within and spaced apart from the edges thereof, the individual locking members of any one set having a general tongue configuration, the free ends of the tongues being directed toward each other, thelength of the tongues being substantially equal, and the bases of the tongues being substantially equal in lateral extension, so that the joint, resulting from sliding one tongue under the other tongue and into the slit in the sheet material created by the provision of the latter tongue, and vice versa, until the respective bases of the tongues serve as mutually limiting stops, will eifectively retain the structure in carton form during use and will afford readiness of disassembly to flat blank status, said individual locking members of any one set being disposed in such relation to their respective panels that an edge of one of such panels lies parallel to and in abutting relation with the line of fold defining the edge of the other of such panels at which the latter is integrally related to the component structure.

4. A compartmented carton comprising a prepared blank of foldable sheet material, said blank having a peripheral configuration and fold lines across its body to form a set of serially, integrally related body panels and closure members for the compartments extending respectively from the top and from the bottom of appropriate body panels, the said blank, further, being folded on itself in general spiral formation to produce the desired number of compartments for the completed carton, locking means disposed in a pair of contiguously positioned panels to secure such panels to each other and to retain the structure in assembled status, said locking means comprising at least one set of two individual locking members provided for mutual coordination, each locking member being formed integral with and being surrounded by the sheet material of the blank, and each locking member, further, comprising both a male and a female formation, the male formation of one of a set of members being adapted for locking coordination with the female formation of the other of the set of members, so that the bases of the respective male members provide mutually limiting stops, the respective male members being of substantially equal extensions, and said individual locking members of any one set being disposed, in such relation to their respective panels, that an edge of one of such panels lies parallel to and in abutting relation with the line of fold defining the edge of the other of such panels at which the latter is integrally related to the component structure.

MARSHALL I. WILLIAMSON. 

